How do fleas choose a victim? - briefly
Fleas locate hosts by detecting body heat, carbon‑dioxide, and movement, then use their jumping ability to reach the nearest animal. They preferentially bite warm‑blooded mammals with dense fur or hair, which provide shelter and a reliable blood source.
How do fleas choose a victim? - in detail
Fleas locate a suitable host through a combination of sensory cues and behavioral strategies.
First, they detect carbon dioxide emitted by warm‑blooded animals. Specialized receptors on the flea’s antennae sense the gas gradient, guiding the insect toward potential prey.
Second, they respond to body heat. Thermoreceptors detect temperature differences as small as 0.5 °C, allowing fleas to discriminate between living tissue and the surrounding environment.
Third, they are attracted to host odors. Volatile compounds such as lactic acid, ammonia, and fatty acids, released through sweat and skin secretions, activate olfactory receptors. These chemicals vary among species, influencing flea preference for specific mammals or birds.
Fourth, they sense movement and vibrations. Mechanoreceptors pick up rhythmic motions generated by breathing or walking, helping fleas pinpoint a precise attachment site.
Finally, once on the host’s surface, fleas use their powerful hind legs to jump onto hair or fur, then crawl to areas with thin skin or high blood flow, such as the neck, groin, or tail base.
The selection process can be summarized as:
- Detection of CO₂ gradient
- Sensing of thermal cues
- Recognition of host‑specific odorants
- Perception of mechanical disturbances
- Physical maneuvering to optimal feeding location
These mechanisms operate together, enabling fleas to efficiently identify and exploit appropriate hosts in diverse environments.